The use of hydrodynamic bearings in many contexts such as spindle motors for disc drives has become increasingly popular. In a hydrodynamic bearing, a lubricating fluid such as air, gas or oil provides a bearing surface between two relatively rotating members, typically a shaft and surrounding sleeve. Hydrodynamic bearings are characterized by establishing a bearing interface over a large surface area in comparison to a ball bearing assembly which comprises a series of point interfaces. This is desirable because the increased bearing surface reduced wobble or runout between the rotating and fixed members. However, this increased bearing surface also leads to a problem, in that the gap between the fixed and rotating surface can be very small, in the order of 2-7 .mu.m size gaps. Thus, the tolerances in a hydrodynamic bearing are roughly five times smaller than in a ball bearing. A fixture which can accurately and repeatably set these gaps while allowing for high speed assembly is highly desirable.